<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
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  <style>
    html,
    body {
      margin: 0;
    }
  </style>
  <body>
    <!--
    vw/vh: 相对于屏幕视口宽高计算，类似定位：% => absolute，vh/vw => fixed
    值： 0-100
 -->
    <!-- <div style="width: 50vw; height: 50px; background-color: red">
  <div style="width: 50%; height: 50px; background-color: blue"></div>
  <div style="width: 50vw; height: 50px; background-color: green"></div>
</div> -->

    <!--
    375的设计稿中，宽为100px的元素
    100/375 * 100
 -->
    <div
      style="width: 26.666666666666666vw; height: 50px; background: cyan"
    ></div>
  </body>
</html>
